Stuck on "USPS Awaiting Item" for 18 Days

In this case I am the sender. I created labels for two packages on August 24th. I was unable to send out the items until later because they were in my old apartment 4 hours away. On September 2nd I had them picked up from my new place, and I got a confirmation email about it. Fast forward to today, USPS is still not showing that they've even received the packages. The buyers are asking me about it and one of them wants their money back. Is there even anything I can do in this situation?